Combine the Italian Dressing and Worcestershire sauce. Coat the tenderloin with the marinade and wrap in plastic wrap. Refrigerate overnight.
Prepare the charcoal according to the directions on the grill for slow barbecuing.
Sprinkle the steak seasoning over the entire tenderloin and cook on the prepared grill for 1-2 hours, until an internal temperature of 125 degrees is achieved.
Allow the meat to rest for 10 minutes before slicing and serving.
Yield: 10-14 servings